Javascript: 自己動手做shuffle，隨機置換陣列內的成員

gistfile1.js

function shuffle(array){
  var myLength = array.length, temp, index
  while(myLength > 0){
    index = Math.floor(Math.random()*myLength);
    myLength--; //範圍不斷縮減，以防止已改變的成員又做更動
    temp = array[myLength];
    array[myLength] = array[index];
    array[index] = temp;
  }
  return array;
}

//如果要當成物件方法

Array.prototype.shuffle = function (){
  var array = this;
  var myLength = array.length, temp, index
  while(myLength > 0){
    index = Math.floor(Math.random()*myLength);
    myLength--;
    temp = array[myLength];
    array[myLength] = array[index];
    array[index] = temp;
  }
  return array;
};